nono : say "no no" to intruders

This is a tool to parse logs and ban ip when they have inappropriate behaviour.

First, you need to setup pf and create a table of banned ip :

block in quick on egress from <bot> to any

If you don't want to run nono as root (it's probably better), create a dedicated user:

# useradd -s /sbin/nologin -m -d /var/empty _nono

Then, setup doas so _nono don't need to enter its password :

permit nopass _nono cmd /sbin/pfctl

Once ready, you can pipe with tail -f any logs to nono:

tail -f /var/log/authlog /var/log/maillog | nono.awk

An example nono.sh is included. It can be started at boot in /etc/rc.local or edit root's crontab :

# crontab -e
@reboot /usr/local/bin/nono.sh

Options

Set options with flags -v var=something. Available options are:

TRIES=5 : Maximum attemps an IP can do.
BANCMD=“doas -u _nono pfctl -T add -t bot” : command to ban an IP. Set to “echo” to just see what happens.
KILLSTATE=“doas -u _nono pfctl -k ” : command to kill all states with an ip
IGNORE=/etc/nono.ignore : file containing ignored IP, one per line.

You may want to set a cron task to release IP after some time :

pfctl -t bot -T expire "$(( 60 * 60 * 24 * $EXPIRE_DAYS ))"

Previous attempt to build such tool was named vilan : https://framagit.org/prx/vilain